Tim Woolmer, founder and chief technology officer, believes his axial-flow motors could be a game changer for mobility
In July, LIVE (formerly Yokeless And Segmented Armature), a British electric motor startup with a revolutionary axial-flow motor, was acquired by Mercedes-Benz. The acquisition didn’t exactly attract huge press attention, as few other details were announced. But YASA is likely to be an entity worth seeing.
Founded in 2009 after its separation from Oxford University, YASA will now develop ultra-high-performance electric motors for the Mercedes-Benz AMG.EA all-electric platform. It will remain in the UK as a wholly owned subsidiary, serving both Mercedes-Benz and existing customers such as Ferrari. The company will retain its own brand, equipment, facilities and location in Oxford.
YASA axial flow electric motors generated interest in the electric vehicle industry due to their efficiency, high power density, small size and low weight.
In contrast, the “radial” electric motor design is more common in today’s electric vehicle market. Even Tesla relies on radial electric motors, a technology inherited from more than 40 years with very little to offer in terms of innovation.
But YASA’s axial flow design, which has very thin segments, means that they can be combined into powerful single-drive units. This makes them a third the weight of other electric motors, more efficient and with power densities 3 times higher than Tesla.
Tim woolmer, Founder and CTO of YASA, invented this very new approach to electric motor design. I caught up with it to find out what’s next.
TC: What is the trip so far?
TW: We started a little over 12 years ago with a single mission: let’s accelerate electric cars, let’s do everything possible to make electric cars faster. Now we have been in a 20-year revolution for 10 years, every new car sold in 10 years will be electric, without a doubt. There is nothing more exciting for an engineer than a period of revolution because the speed of innovation is the important thing. What’s so exciting for us is that we can innovate quickly, and that’s where the partnership with Mercedes is really interesting.
TC: What was different about the engine that you came up with?
TW: We started with a blank sheet of paper at the beginning of my PhD. And the idea was to say, what could be created for the electric car industry in 10 or 15 years from now that they would need, that we could deliver. Something that was lighter, more efficient, mass-producible in volume. Back in the 2000s, axial-flow motors weren’t very common, but by combining axial-flow technology and making a couple of small tweaks with some new materials, I basically stumbled upon this new design that we call YASA: Yokeless And Segmented. Armature. It takes what is a lightweight topology in axial flow and makes it even lighter, about half again. There is an advantage because the rotors rotate with a larger diameter. So essentially torque is force times diameter, so for the same force, you get more torque. So if you double your diameter, you get double the torque for the same amount of materials. So that’s the benefit of axial flow.
TC: You did this with a deal with Mercedes, what’s next?
TW: We are basically a wholly owned subsidiary. We are going to use the industrialization power of Mercedes. But the key is, if you look at how technologies seep into automotive, they start in the luxury sector, like Ferraris and McLarens, and then seep into the mainstream sector and then move to higher volumes after that. That’s a space where Mercedes is world-class in terms of its industrialization, so that’s the kind of idea behind the partnership.
TC: What else can you do from here?
TW: We will have a very tall, high-powered, low-density, and lightweight engine so that we can explore sports performance alongside high levels of industrialization. That puts us in a really unique position for all kinds of things.
Although shy about his future plans, Woolmer is certainly someone to be reckoned with in the electric vehicle and electric motor space. After the acquisition, YASA released this video: